So I thru it back 2gether & put in a 27.5 pilot & 85 main jet in. Fired straight up. Idling higher. Quieter, not so much "ring ding". Took it for 15 minute ride, taking it easy with new piston & rings. 85 main jet isnt far off, may need 30 pilot. Comes on strong from 1/3 throttle. Its gunna b quick, I could tell that even taking it easy. I'll grab a couple of new plugs in the morning & get this jetting all sorted & put some decent miles on it. Cheers
reed kit
- Thread starter john8460
- Start date
Ok, so I pulled the plug. May need bigger than 85 main jet. I didnt take it over 2/3 throttle as I was taking it easy, so it wasnt 2 where it'd start running outta carb if its 2 lean but by the plug I think it is so I'll get new plugs & have a good go at it this arvo. Cheers
Well by the time I knocked off this arvo it 2 late 2 do anything but I have set aside 2morra arvo (friday) & all weekend 2 get the jetting properly sorted & give it a decent workout. The next thing then will b 2 liquid cool the head. The RSE design will b easy 2 enclose the cooling fins. I'll put a small thermostat on the exit & run an impeller pump off the reduction gear drive, & use a small raiator with 13lb pressure cap. Coolant will b Ethylene Glycol. Cheers
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So I put in a 30 pilot & 87.5 main. Havent done the air screw yet. Strong & progressive right thru till it runs flat just under wide open, so I'll put in a 90 main & c how it goes. Venice is right, 100%. If ur thinking reeds, think "Ported Piston & Boost Ported Jug". This is where the gains r, & it is noticeable gains 2. Cheers
ok, it had overrev returning 2 idle when blipping the throttle which indicates lean in this area so I put in 32.5 pilot & its good. Nice idle exhaust "blat" & just a little blue smoke. The plug showed still lean a little so I put in 90 main. Very strong down low to 2/3 throttle, very strong. Jetting or needle height still needs work but its close. I'll let it cool & pull the plug. Cheers
well the plug aint 2 bad, tho I've noticed with it breathing thru 180 degrees, going up or down 1 jet size has a lot less effect than breathing thru 60degrees. I have a 92.5 main so I'll put that in & tune for best WOT performance between 90 & 92.5, which is the biggest I have, & its got the biggest pilot I have in @ 32.5 but that 1's good so ya can b lucky sometimes. Cheers
Ok, with 32.5 pilot & 92.5 main jets its good. Very tracable from idle right thru. A 30% power gain, for sure, maybe better. Still slight hiccup @1/3 throttle transition from pilot to main but I havent done the air screw yet & that'll get it sorted. I'll check the plug when cools. Still just not getting WOT quite, but I think its running outta pipe as I extended the header so I'll knock 3/8" off it & c. Cheers
Well the plug after a good run is a light tan. I wouldnt like it any leaner. Breathing thru 60# changing 1 jet size makes a big difference. Breathing thru 180#, going 1 jet size only makes a small difference so it makes it easier to really dial in properly. I'll order a 95 & 97.5, maybe even a 100 main jet so I can get it spot on. Its acceptable as is, but just. I little richer would b good & run cooler. Cheers
So, do I recommend this? Definitely. 4 the cost of reeds, some work with a drill, dremel & carbide cutter, a 10x14x15 small end bearing, a hi comp head, a sizeable upjet & u have a much stronger, smoother motor. Build the cdi I had posted or buy a Jag 1, add a xchamber tuned where u want & a 16mm carb that is tuneable & so much the better. I am very happy with the gains. Cheers
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I will try 2 get drawings of the piston & cylinder portwork posted as I think that even on a stock motor, for cost, this is definitely a worthwhile mod. I would recommend changing the small end bearing to 10x14x15 as it will b under increase loads right thru, so u dont want the bearing drifting half outta the rod end, & u'd have it that far apart 2 do this anyway. Cheers
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Ok, I've ordered 95, 97.5 & 100 main jets. With the mixture just acceptable I'll wait the few days til they're here, then tune 4 best WOT performance, then do the air screw & needle height & do some good long rides. Its a new piston & rings so it'll loosen up a little, not heaps cause its the same jug with a light hone cross hatching. Then we'll c wot she'll do. Cheers
Ok, 95, 97.5 & 100 main jets turned up this afternoon, if there's enough time after knock off I'll have a go at, otherwise I got tomorrow off so I'll have time to get the mixture & needle height spot on. Pretty sure these 3 jets will have it covered. Cheers
Ok, I put in 97.5 main jet, still 32.5 pilot, needle C-clip in the middle of 5 positions, air screw not yet done (VM 16 Mikuni) & took for 15 or 20 minute ride. Some 4 stroking in lower gears when it isnt under load, but not much. I'll let it cool & check the plug, maybe 95 main would b better. Still 1/2 of today left to get it sorted, then give it a really good workout over the weekend. Cheers
Well its just a shade rich by the plug color so 95 main will b spot on. The air screw is 2 1/8 turns out, where its been from the previous setup but I'll put the 95 main in, get it up to good running temp & do the air screw & needle height & get some decent miles on it. I'm glad I have the 97.5 & 100 main jets, we're still in winter here & its 28 degrees Celcius outside 2day so its gunna b a cracker of a summer. I'll run it a little rich during the hotter months 2 keep it cooller. Seriously, do this mod. Cheers
Thanks for posting all your work with the reed. I bought one and have not been able to get it running how it should, I’m getting better power with out it, I got tired of changing out jets and carb tunning trying to get it Wright, maybe I'll try again at a latter date.
Hi Spanners, I'm in SE QLD. When I first put them on I had 2 downjet a little & it was touchy gettin it right. After doing all the porting it was a lot easier upjetting as each jet size only makes a small difference. They're pretty easy to do (ports) & its well worth it, heaps stronger right from idle. My motor came from Zbox, I just grabbed a new piston/rings & did that first, then did the old jug with a dremel,,, an honest 30% increase. Cheers
Hey Spanners, if u have the NT carb with stock air cleaner either get a better air cleaner or drill a heap of holes in the back of the plastic cover. B4 I put the mikuni on I had NT. I had trouble geting it jetted perfectly til I put an SBP aircleaner on & realized the stock 1 had been restricting it at hi rpm. Could get it jetted right straight away & picked up 10kph at least, just from changing air cleaner. Also open up the intake port ceiling to let the upper reed have clearance. Cheers
I have a Rock solid motor, I also did some more port work to it, and it has a delorto clone with the air mixture screw. I played with it for a couple of days trying to get the reed to come in to play , I got a bit frustrated and gave up on it for the time being, I was thinking of trying it with a different carby and after read your post lifting the roof in the intake port. It sounds like you got the results I was trying achieve.
Cheers spanners
Cheers spanners
Hi Spanners, yeah, opening it up lets the top reed open properly. I cut it @ 90 degrees from the external manifold mating face, depth 8mm, width 20.5mm. Take care not 2 break thru. To really get the gains u need to cut the 2 ports in the piston to same width as ur intake port, & take 5mm of the bottom of the skirt 2 same width. Changes the whole character of the motor & it pulls right from idle. Cheers